The only way that you will get your printer to work on Windows 7 is to install it on either Microsoft's virtual PC or Virtualbox, if your version of Windows does not support Microsoft's virtual PC. This is not an ideal solution but is a convenient way of being able to use your printer.
I just had an idea, the printer is a Parallel one so the computer does not know what printer is actually connected to it. Try installing a printer driver for a FX850 or a FX80 or a printer driver that supports PCL 5e emulation.